Figure 1

XRD patterns of WxV1−xO2 prepared at 280 °C with W doping levels ranging from 0.0 to 2.0 at% for different duration of hydrothermal time.
The filled dark blue diamond and olive star are characteristic peaks for B and A phase of VO2 respectively. The red and black columns belong to standard pattern in JCPDS card No. 65–2358 for VO2(M) and No. 76–0677 for VO2(R) respectively.